Aerial vehicle optical sensor configuration

ABSTRACT

Described is an aerial vehicle, such as an unmanned aerial vehicle (“UAV”), that includes a plurality of sensors, such as stereo cameras, mounted along a perimeter frame of the aerial vehicle and arranged to generate a scene that surrounds the aerial vehicle. The sensors may be mounted in or on winglets of the perimeter frame. Each of the plurality of sensors has a field of view and the plurality of optical sensors are arranged and/or oriented such that their fields of view overlap with one another throughout a continuous space that surrounds the perimeter frame. The fields of view may also include a portion of the perimeter frame or space that is adjacent to the perimeter frame.

BACKGROUND

Optical sensors have been used on unmanned aerial vehicles (UAVs) tomeasure or capture images of space around the aerial vehicle. Forexample, cameras have been used to detect objects around UAVs. Measuringspace around UAVs with optical sensors has traditionally been limited bythe range of the optical sensors, the geometries of the UAVS and mountsfor optical sensors, and the amount of optical sensors on a UAV.

Mounting optical sensors at traditional mounting locations on UAVs, suchas on a gimbal below the frame of the UAV, results in spaces around theUAV that cannot be measured or “blind spots.” For example, if sensorsare mounted from a structure extending directly above or below themiddle of the UAV, blind spots may be present near the UAV, above orbelow the sensors, and/or above or below the UAV. Blind spots areundesirable because an object in a blind spot cannot be detected.

Blind spots may be reduced by mounting additional optical sensors thatare directed toward the blind spots; however, adding an optical sensorand its corresponding wiring and mounting hardware increases the weightof the UAV. In addition, mounting optical sensors can increase the dragand otherwise negatively impact flight, takeoff, and/or landingperformance. Also, adding additional optical sensors and their mountinghardware can create additional blind spots. In addition, adding sensorsto a UAV may increase the computing resources, and relatedly, the power,that is required to process the data provided by the sensors.

BRIEF DESCRIPTION OF THE DRAWINGS

The detailed description is set forth with reference to the accompanyingfigures. In the figures, the left-most digit(s) of a reference numberidentifies the figure in which the reference number first appears.

FIG. 1 depicts a view of an aerial vehicle configuration, according toan implementation.

FIGS. 2A and 2B depict views of optical sensors mounted to front andrear winglets of an aerial vehicle, respectively, according to animplementation.

FIG. 3 depicts a view of a plurality of optical sensors and a continuousspace that horizontally surrounds an aerial vehicle, according to animplementation.

FIG. 4 depicts a side view of an aerial vehicle that includes an opticalsensor with a field of view that extends into a space below the aerialvehicle, according to an implementation.

FIG. 5 is a flow diagram illustrating an example process for generatinga scene representation of a continuous space horizontally surrounding anaerial vehicle, according to an implementation.

FIG. 6 is a block diagram of an illustrative implementation of an aerialvehicle control system that may be used with various implementations.

While implementations are described herein by way of example, thoseskilled in the art will recognize that the implementations are notlimited to the examples or drawings described. It should be understoodthat the drawings and detailed description thereto are not intended tolimit implementations to the particular form disclosed but, on thecontrary, the intention is to cover all modifications, equivalents andalternatives falling within the spirit and scope as defined by theappended claims. The headings used are for organizational purposes onlyand are not meant to be used to limit the scope of the description orthe claims. As used throughout this application, the word “may” is usedin a permissive sense (i.e., meaning having the potential to), ratherthan the mandatory sense (i.e., meaning must). Similarly, the words“include,” “including,” and “includes” mean “including, but not limitedto.” As used herein, the term “coupled” may refer to two or morecomponents connected together, whether that connection is permanent(e.g., welded) or temporary (e.g., bolted), direct or indirect (i.e.,through an intermediary), mechanical, chemical, optical, or electrical.As used herein, “horizontal” flight refers to flight traveling in adirection substantially parallel to the ground (i.e., sea level), andthat “vertical” flight refers to flight traveling substantially radiallyoutward from the earth's center. It should be understood by those havingordinary skill that trajectories may include components of both“horizontal” and “vertical” flight vectors. As used herein in connectionwith angles, “approximately” means within +/−10 degrees.

DETAILED DESCRIPTION

This disclosure describes a configuration of an aerial vehicle, such asan unmanned aerial vehicle (“UAV”), having a plurality of sensors, suchas optical sensors, cameras, etc., located along a perimeter frame ofthe aerial vehicle. The sensors may be attached to winglets or otherstructures of the perimeter frame. Each sensor may include a stereocamera that is oriented or arranged in a configuration around aperimeter of the aerial vehicle such that an edge of a field of view ofthe stereo camera is adjacent, parallel, and/or encompasses a portion ofthe perimeter frame of the aerial vehicle. Likewise, the field of viewof each stereo camera of the configuration overlaps with a field of viewof at least one other stereo camera of the configuration. In someimplementations, a horizontal alignment of a field of view of the stereocameras is offset with respect to a direction of travel. Theconfigurations disclosed herein may provide for a scene to be generatedthat represents a continuous space that surrounds (e.g., horizontally orvertically) the aerial vehicle using as few as four sensors. Theconfigurations disclosed herein may provide for an outer surface of theperimeter frame or space close to an outer surface of the perimeterframe of the aerial vehicle to be included within the fields of views ofthe sensors, which may provide for detection of objects at spaces closeto the aerial vehicle and reduced blind spots.

FIG. 1 illustrates a view of an aerial vehicle 100 according to animplementation. In some implementations, the aerial vehicle 100 is aUAV. As illustrated, the aerial vehicle 100 includes a perimeter frame104 that includes a front wing 120, a lower rear wing 124, an upper rearwing 122, and two horizontal side rails 130-1, 130-2. The horizontalside rails 130 are coupled to opposing ends of the front wing 120 andopposing ends of the upper rear wing 122 and lower rear wing 124. Insome implementations, the coupling may be with a corner junction, suchas the front left corner junction 131-1, the front right corner junction131-2, the rear right corner junction 131-3, and the rear left cornerjunction 131-4. In such implementations, the corner junctions are partof the perimeter frame 104.

The components of the perimeter frame 104, such as the front wing 120,lower rear wing 124, upper rear wing 122, side rails 130-1, 130-2, andcorner junctions 131 may be formed of any one or more suitablematerials, such as graphite, carbon fiber, aluminum, titanium, etc., orany combination thereof. In the illustrated example, the components ofthe perimeter frame 104 of the aerial vehicle 100 are each formed ofcarbon fiber and joined at the corners using corner junctions 131. Thecomponents of the perimeter frame 104 may be coupled using a variety oftechniques. For example, if the components of the perimeter frame 104are carbon fiber, they may be fitted together and joined using secondarybonding, a technique known to those of skill in the art. In otherimplementations, the components of the perimeter frame 104 may beaffixed with one or more attachment mechanisms, such as screws, rivets,latches, quarter-turn fasteners, etc., or otherwise secured together ina permanent or removable manner.

The front wing 120, lower rear wing 124, and upper rear wing 122 arepositioned in a tri-wing configuration and each wing provides lift tothe aerial vehicle 100 when the UAV is moving in one or more directions.For example, the wings may each have an airfoil shape that causes liftdue to the airflow passing over the wings during horizontal flight.

Opposing ends of the front wing 120 may be coupled to a corner junction131, such as the front right corner junction 131-2 and front left cornerjunction 131-1. In some implementations, the front wing may include oneor more flaps 127 (or “ailerons”), that may be capable of adjusting thepitch, yaw, and/or roll of the aerial vehicle 100 alone or incombination with the lifting motors 106, lifting propellers 102,thrusting motors 110, thrusting propellers 112, and/or other flaps onthe rear wings, discussed below. In one or more implementations, theflaps 127 may be used as a protective shroud to further hinder access tothe lifting propellers 102 by objects external to the aerial vehicle100. For example, when the aerial vehicle 100 is moving in a verticaldirection or hovering, the flaps 127 may be extended to increase a sizeof a protective barrier around a portion of the lifting propellers 102.

In some implementations, the front wing 120 may include two or morepairs of flaps 127, as illustrated in FIG. 1. In other implementations,for example, if there is no front thrusting motor 110-1, the front wing120 may only include a single flap 127 that extends substantially thelength of the front wing 120. If the front wing 120 does not includeflaps 127, the lifting motors 106 and lifting propellers 102, thrustingmotors 110, thrusting propellers 112 and/or flaps of the rear wings maycontrol the pitch, yaw, and/or roll of the aerial vehicle 100 duringflight.

Opposing ends of the lower rear wing 124 may be coupled to a cornerjunction 131, such as the rear right corner junction 131-3 and rear leftcorner junction 131-4. The rear right corner junction 131-3 and the rearleft corner junction 131-4 may be winglets. In some implementations, thelower rear wing may include one or more flaps 123, that may adjust thepitch, yaw and/or roll of the aerial vehicle 100 alone or in combinationwith the lifting motors 106, lifting propellers 102, thrusting motors110, thrusting propellers 112, and/or the flaps 127 of the front wing.In some implementations, the flaps 123 may also be used as a protectiveshroud to further hinder access to the lifting propellers 102 by objectsexternal to the aerial vehicle 100. For example, when the aerial vehicle100 is moving in a vertical direction or hovering, the flaps 123 may beextended, similar to the extending of the front flaps 127 of the frontwing 120.

In some implementations, the rear wing 124 may include two or more flaps123, as illustrated in FIG. 1 or two or more pairs of flaps,respectively. In other implementations, for example if there is no rearthrusting motor 110-2 mounted to the lower rear wing, the rear wing 124may only include a single flap 123 that extends substantially the lengthof the lower rear wing 124. In other implementations, if the lower rearwing includes two thrusting motors, the lower rear wing may beconfigured to include three flaps 123, one on either end of the lowerrear wing 124, and one between the two thrusting motors mounted to thelower rear wing 124.

Opposing ends of the upper rear wing 122 may be coupled to a cornerjunction 131, such as the rear right corner junction 131-3 and rear leftcorner junction 131-4. In some implementations, like the lower rear wing124, the upper rear wing 122 may include one or more flaps (not shown)or ailerons, that may adjust the pitch, yaw and/or roll of the aerialvehicle 100 alone or in combination with the lifting motors 106, liftingpropellers 102, thrusting motors 110, thrusting propellers 112, and/orother flaps of other wings (not shown). In some implementations, theflaps may be capable of forming a protective shroud that may hinderaccess to the lifting propellers 102 by objects external to the aerialvehicle 100. When the aerial vehicle 100 is moving in a verticaldirection or hovering, the flaps may be extended, similar to theextending of the front flaps 127 of the front wing 120 or the flaps 123of the lower rear wing.

The front wing 120, lower rear wing 124, and upper rear wing 122 may bepositioned and sized proportionally to provide stability to the aerialvehicle while the aerial vehicle 100 is moving in a horizontaldirection. For example, the lower rear wing 124 and the upper rear wing122 are stacked vertically such that the vertical lift vectors generatedby each of the lower rear wing 124 and upper rear wing 122 are closetogether, which may be destabilizing during horizontal flight. Incomparison, the front wing 120 is separated from the rear wingslongitudinally such that the vertical lift vector generated by the frontwing 120 acts with the vertical lift vectors of the lower rear wing 124and the upper rear wing 122, providing efficiency, stabilization andcontrol.

In some implementations, to further increase the stability and controlof the aerial vehicle 100, one or more winglets 121, or stabilizer arms,may also be coupled to and included as part of the perimeter frame 104.In the example illustrated regarding FIG. 1, there are two frontwinglets 121-1 and 121-2 mounted to the underneath side of the frontleft corner junction 131-1 and the front right corner junction 131-2,respectively. The winglets 121 extend in a downward directionapproximately perpendicular to the front wing 120 and horizontal siderails 130. Likewise, the two rear corner junctions 131-3, 131-4 are alsoformed and operate as winglets providing additional stability andcontrol to the aerial vehicle 100 when the aerial vehicle 100 is movingin a horizontal direction.

The winglets 121 and the rear corner junctions 131-3, 131-4 may havedimensions that are proportional to the length, width, and height of theaerial vehicle 100 and may be positioned based on the approximate centerof gravity of the aerial vehicle 100 to provide stability and control tothe aerial vehicle 100 during horizontal flight. In one implementation,the aerial vehicle 100 may be approximately 64.75 inches long from thefront of the aerial vehicle 100 to the rear of the aerial vehicle 100and approximately 60.00 inches wide. In such a configuration, the frontwing 120 has dimensions of approximately 60.00 inches by approximately7.87 inches. The lower rear wing 124 has dimensions of approximately60.00 inches by approximately 9.14 inches. The upper rear wing 122 hasdimensions of approximately 60.00 inches by approximately 5.47 inches.The vertical separation between the lower rear wing and the upper rearwing is approximately 21.65 inches. The winglets 121 are approximately6.40 inches wide at the corner junction with the perimeter frame of theUAV, approximately 5.91 inches wide at the opposing end of the wingletand approximately 23.62 inches long. The rear corner junctions 131-3,131-4 are approximately 9.14 inches wide at the end that couples withthe lower rear wing 124, approximately 8.04 inches wide at the opposingend, and approximately 21.65 inches long. The overall weight of theaerial vehicle 100 is approximately 50.00 pounds.

Coupled to the interior of the perimeter frame 104 is a central frame107. The central frame 107 includes a hub 108 and motor arms 105 thatextend from the hub 108 and couple to the interior of the perimeterframe 104. In this example, there is a single hub 108 and four motorarms 105-1, 105-2, 105-3, and 105-4. Each of the motor arms 105 extendfrom approximately a corner of the hub 108 and couple or terminate intoa respective interior corner of the perimeter frame. In someimplementations, each motor arm 105 may couple into a corner junction131 of the perimeter frame 104. Like the perimeter frame 104, thecentral frame 107 may be formed of any suitable material, such asgraphite, carbon fiber, aluminum, titanium, etc., or any combinationthereof. In this example, the central frame 107 is formed of carbonfiber and joined at the corners of the perimeter frame 104 at the cornerjunctions 131. Joining of the central frame 107 to the perimeter frame104 may be done using any one or more of the techniques discussed abovefor joining the components of the perimeter frame 104.

Lifting motors 106 are coupled at approximately a center of each motorarm 105 so that the lifting motor 106 and corresponding liftingpropeller 102 are within the perimeter frame 104. In one implementation,the lifting motors 106 are mounted to an underneath or bottom side ofeach motor arm 105 in a downward direction so that the propeller shaftof the lifting motor that mounts to the lifting propeller 102 is facingdownward. In other implementations, as illustrated in FIG. 1, thelifting motors 106 may be mounted to a top of the motor arms 105 in anupward direction so that the propeller shaft of the lifting motor thatmounts to the lifting propeller 102 is facing upward. In this example,there are four lifting motors 106-1, 106-2, 106-3, 106-4, each mountedto an upper side of a respective motor arm 105-1, 105-2, 105-3, and105-4.

In some implementations, multiple lifting motors may be coupled to eachmotor arm 105. For example, while FIG. 1 illustrates a quad-copterconfiguration with each lifting motor mounted to a top of each motorarm, a similar configuration may be utilized for an octo-copter. Forexample, in addition to mounting a lifting motor 106 to an upper side ofeach motor arm 105, another lifting motor may also be mounted to anunderneath side of each motor arm 105 and oriented in a downwarddirection. In another implementation, the central frame 107 may have adifferent configuration, such as additional motor arms. For example,eight motor arms may extend in different directions and a lifting motormay be mounted to each motor arm.

The lifting motors may be any form of motor capable of generating enoughrotational speed with the lifting propellers 102 to lift the aerialvehicle 100 and any engaged payload, thereby enabling aerial transportof the payload.

Mounted to each lifting motor 106 is a lifting propeller 102. Thelifting propellers 102 may be any form of propeller (e.g., graphite,carbon fiber) and of a size sufficient to lift the aerial vehicle 100and any payload engaged by the aerial vehicle 100 so that the aerialvehicle 100 can navigate through the air, for example, to deliver apayload to a delivery location. For example, the lifting propellers 102may each be carbon fiber propellers having a dimension or diameter oftwenty-four inches. While the illustration of FIG. 1 shows the liftingpropellers 102 all of a same size, in some implementations, one or moreof the lifting propellers 102 may be different sizes and/or dimensions.Likewise, while this example includes four lifting propellers 102-1,102-2, 102-3, 102-4, in other implementations, more or fewer propellersmay be utilized as lifting propellers 102. Likewise, in someimplementations, the lifting propellers 102 may be positioned atdifferent locations on the aerial vehicle 100. In addition, alternativemethods of propulsion may be utilized as “motors” in implementationsdescribed herein. For example, fans, jets, turbojets, turbo fans, jetengines, internal combustion engines, and the like may be used (eitherwith propellers or other devices) to provide lift for the UAV.

In addition to the lifting motors 106 and lifting propellers 102, theaerial vehicle 100 may also include one or more thrusting motors 110 andcorresponding thrusting propellers 112. The thrusting motors andthrusting propellers may be the same or different than the liftingmotors 106 and lifting propellers 102. For example, in someimplementations, the thrusting propellers may be formed of carbon fiberand be approximately eighteen inches long. In other implementations, thethrusting motors may utilize other forms of propulsion to propel theaerial vehicle. For example, fans, jets, turbojets, turbo fans, jetengines, internal combustion engines, and the like may be used (eitherwith propellers or with other devices) as the thrusting motors.

The thrusting motors and thrusting propellers may be oriented atapproximately ninety degrees with respect to the perimeter frame 104 andcentral frame 107 of the aerial vehicle 100 and utilized to increase theefficiency of flight that includes a horizontal component. For example,when the aerial vehicle 100 is traveling in a horizontal direction, thethrusting motors may be engaged to provide a horizontal thrust force viathe thrusting propellers to propel the aerial vehicle 100 horizontally.As a result, the speed and power utilized by the lifting motors 106 maybe reduced. Alternatively, in selected implementations, the thrustingmotors may be oriented at an angle greater or less than ninety degreeswith respect to the perimeter frame 104 and the central frame 107 toprovide a combination of thrust and lift.

In the example illustrated in FIG. 1, the aerial vehicle 100 includestwo thrusting motors 110-1, 110-2 and corresponding thrusting propellers112-1, 112-2. Specifically, in the illustrated example, there is a frontthrusting motor 110-1 coupled to and positioned near an approximatemid-point of the front wing 120. The front thrusting motor 110-1 isoriented such that the corresponding thrusting propeller 112-1 ispositioned inside the perimeter frame 104. The second thrusting motor iscoupled to and positioned near an approximate mid-point of the lowerrear wing 124. The rear thrusting motor 110-2 is oriented such that thecorresponding thrusting propeller 112-2 is positioned inside theperimeter frame 104.

While the example illustrated in FIG. 1 illustrates the aerial vehicle100 with two thrusting motors 110 and corresponding thrusting propellers112, in other implementations, there may be fewer or additionalthrusting motors and corresponding thrusting propellers. For example, insome implementations, the aerial vehicle 100 may only include a singlerear thrusting motor 110 and corresponding thrusting propeller 112. Inanother implementation, there may be two thrusting motors andcorresponding thrusting propellers mounted to the lower rear wing 124.In such a configuration, the front thrusting motor 110-1 may be includedor omitted from the aerial vehicle 100. Likewise, while the exampleillustrated in FIG. 1 shows the thrusting motors oriented to positionthe thrusting propellers inside the perimeter frame 104, in otherimplementations, one or more of the thrusting motors 110 may be orientedsuch that the corresponding thrusting propeller 112 is oriented outsideof the perimeter frame 104.

The perimeter frame 104 may protect the aerial vehicle 100 from foreignobjects by inhibiting access to the lifting propellers 102 from the sideof the aerial vehicle 100 and may increase the structural integrity ofthe aerial vehicle 100. If the aerial vehicle 100 is travelinghorizontally and collides with a foreign object (e.g., wall, building),the impact between the aerial vehicle 100 and the foreign object will bewith the perimeter frame 104, rather than a propeller. Likewise, becausethe perimeter frame 104 is interconnected with the central frame 107,the forces from the impact are dissipated across both the perimeterframe 104 and the central frame 107.

The perimeter frame 104 also provides a structure from which one or morecomponents of the aerial vehicle 100 may be mounted on or in.Alternatively, or in addition thereto, one or more components of theaerial vehicle 100 may be mounted or positioned within the cavity of theportions of the perimeter frame 104. For example, one or more antennasmay be mounted on or in the front wing 120. The antennas may transmitand/or receive wireless communications. For example, the antennas may beutilized for Wi-Fi, satellite, near field communication (“NFC”),cellular communication, or any other form of wireless communication.Other components, such as optical sensors (e.g., cameras), time offlight sensors, accelerometers, inclinometers, distance-determiningelements, gimbals, Global Positioning System (GPS) receiver/transmitter,radars, illumination elements, speakers, and/or any other component ofthe aerial vehicle 100 or the aerial vehicle control system (discussedbelow), etc., may likewise be mounted to or in the perimeter frame 104.Likewise, identification or reflective identifiers may be mounted to theperimeter frame 104 to aid in the identification of the aerial vehicle100.

In some implementations, the perimeter frame 104 may also include apermeable material (e.g., mesh, screen) that extends over the top and/orlower surface of the perimeter frame 104 enclosing the central frame107, lifting motors 106, and/or lifting propellers 102.

An aerial vehicle control system 114 is also mounted to the centralframe 107. In this example, the aerial vehicle control system 114 ismounted to the hub 108 and is enclosed in a protective barrier. Theprotective barrier may provide the control system 114 weather protectionso that the aerial vehicle 100 may operate in rain and/or snow withoutdisrupting the control system 114. In some implementations, theprotective barrier may have an aerodynamic shape to reduce drag when theUAV is moving in a direction that includes a horizontal component. Theprotective barrier may be formed of any materials including, but notlimited to, graphite-epoxy, Kevlar, and/or fiberglass. In someimplementations, multiple materials may be utilized. For example, Kevlarmay be utilized in areas where signals need to be transmitted and/orreceived.

Likewise, the aerial vehicle 100 includes one or more power modules 155.In some implementations, the power modules 155 may be positioned insidethe cavity of the side rails 130-1, 130-2. In other implementations, thepower modules 155 may be mounted or positioned at other locations of theUAV. The power modules 155 for the UAV may be in the form of batterypower, solar power, gas power, super capacitor, fuel cell, alternativepower generation source, or a combination thereof. For example, thepower modules 155 may each be a 6000 mAh lithium-ion polymer battery, orpolymer lithium ion (Li-poly, Li-Pol, LiPo, LIP, PLI or Lip) battery.The power module(s) are coupled to and provide power for the aerialvehicle control system 114, the lifting motors 106, the thrusting motors110, the optical sensors 150, and the payload engagement mechanism 154.

In some implementations, one or more of the power modules 155 may beconfigured such that it can be autonomously removed and/or replaced withanother power module while the UAV is landed or in flight. For example,when the UAV lands at a location, the UAV may engage with a chargingmember at the location that will recharge the power module.

As mentioned above, the aerial vehicle 100 may also include a payloadengagement mechanism 154. The payload engagement mechanism 154 may beconfigured to engage and disengage items and/or containers that holditems (payload). In this example, the payload engagement mechanism 154is positioned beneath and coupled to the hub 108 of the perimeter frame104 of the aerial vehicle 100. The payload engagement mechanism 154 maybe of any size sufficient to securely engage and disengage a payload. Inother implementations, the payload engagement mechanism 154 may operateas the container in which it contains item(s). The payload engagementmechanism 154 communicates with (via wired or wireless communication)and is controlled by the aerial vehicle control system 114. Examplepayload engagement mechanisms are described in co-pending patentapplication Ser. No. 14/502,707, filed Sep. 30, 2014, titled “UNMANNEDAERIAL VEHICLE DELIVERY SYSTEM,” the subject matter of which isincorporated by reference herein in its entirety.

A first optical sensor 150, a second optical sensor 151, a third opticalsensor 152, and a fourth optical sensor 153 are coupled (or “secured,”“attached,” “mounted,” etc.) to the perimeter frame 104. The firstoptical sensor 150 and the second optical sensor 151 are coupled to thefront left corner junction 131-1 and the front right corner junction131-2, respectively. As discussed in more detail with respect to FIG.2A, the first optical sensor 150 may be secured to the winglet 121-1 andmay protrude (or “extend”) away from the inner side of the winglet121-1. The second optical sensor 151 may be secured to the winglet 121-2and protrude away from an outer side of the winglet 121-2. The thirdoptical sensor 152 may be mounted to the rear right corner junction131-3 and may protrude away from an outer side of the rear right cornerjunction 131-3. The fourth optical sensor 153 may be mounted to the rearleft corner junction 131-4 and protrude from an inner side of the rearleft corner junction 131-4. In other implementations, sensors may be atother locations, such as wings (e.g., front wing 120, upper wing 122),flaps (e.g., flap 123, 127). For example, a plurality of sensors may bemounted or secured to a single winglet.

The first optical sensor 150 and the second optical sensor 151 arelocated at a bottom portion 143 of the aerial vehicle 100, and the thirdoptical sensor 152 and the fourth optical sensor 153 are located at atop portion 149 of the aerial vehicle 100. The bottom portion 143 of theaerial vehicle 100 is a portion of the perimeter frame 107 that is belowa horizontal centerline 161. The top portion 149 of the aerial vehicle100 is a portion of the perimeter frame 107 above the horizontalcenterline 161.

The optical sensors 150, 151, 152, and 153 may include various types ofsensors such as single lens cameras, stereo cameras, multi-lens cameras,digital still cameras, red, green, blue (RGB) cameras, video cameras,thermographic cameras, infrared sensors, and light detection and ranging(LIDAR). As used herein, “optical sensor” includes sensors capable ofconverting light into electrical signals that are representative orindicative of an object included in the field of view of the opticalsensor. In some implementations, one or more optical sensors may includeor be replaced with other types of sensors, for example, soundnavigation and ranging (SONAR) sensors that may be used. In general, asused herein, “sensor” includes any sensor that is capable of detectingor generating, or being used to detect or generate, a representation ofan object located in a field of view of the optical sensor.

In some implementations, the optical sensor includes a stereo camerawith two or more imaging elements that are capable of being usedtogether to capture or obtain images of three-dimensional space. As usedherein, “imaging element” refers to a device used to record or captureimage data or data that may be used to generate an image. For example,an imaging element may include an optical instrument, such as a digitalcamera. In another example, an imaging element includes a lens used topass light to a sensor and/or detector. In some implementations, astereo camera has a separate image sensor, detector, or film frame foreach lens. In some examples, a single sensor may be used in combinationwith multiple lenses of a stereo camera.

The first optical sensor 150, the second optical sensor 151, the thirdoptical sensor 152, and the fourth optical sensor 153 each may have anangle of view. As used herein, “angle of view” refers to an anglethrough which a detector of an optical sensor is sensitive toelectromagnetic radiation. In one or more implementations, the angles ofview may be adjustable. For example, the angles of view may beadjustable by the aerial vehicle controller 114. Angles of view may bemeasured horizontally, vertically, or diagonally. In someimplementations, the optical sensors 150, 151, 152, and 153 may havehorizontal angles of view that are at least 110 degrees and verticalangles of view that are greater than 60 degrees. In someimplementations, the optical sensors 150, 151, 152, and 153 may havehorizontal angles of view that are each at least 100 degrees. In otherimplementations, the optical sensors 150, 151, 152, and 153 may havehorizontal angles of view that are between 90 and 100 degrees. In someimplementations, optical sensors 150, 151, 152, and 153 have angles ofview that are substantially the same. In other implementations, theangle of view of at least one optical sensor on the aerial vehicle isdifferent from the angles of view of other optical sensors on the aerialvehicle. The angles of view of optical sensors 150, 151, 152, and 153may be selected based on the shape of the aerial vehicle 100 or alocation on the perimeter frame of each respective optical sensor, forexample.

The first optical sensor 150, the second optical sensor 151, the thirdoptical sensor 152, and the fourth optical sensor 153 each may have afield of view. As used herein, “field of view” refers to space in theobservable world that may be measured (or “sensed”) at a time using theoptical sensor. The field of view of an optical sensor may depend on alocation and an orientation of the optical sensor with respect to thevehicle. The field of view of an optical sensor may also depend on theangle of view of the optical sensor. For a stereo camera, each imagingelement may have a field of view, and the stereo camera may have acombined field of view. Unless otherwise indicated from the context, the“field of view” of a stereo camera refers to the common field of viewthat this is defined by common or overlapping portions of one or morefields of view of the imaging elements of the stereo camera.

For a camera sensor, such as a stereo camera, the angle of view andfield of view may depend on one or more properties of the imagingelements of the stereo camera. For example, the focal lengths of lensesof the imaging elements may determine the angle of view of the stereocamera. In some implementations, the field of view of a stereo cameraand the angle of view of the stereo camera may be proportional to oneanother. For example, an optical sensor with a larger angle of view mayhave a larger field of view compared to an optical sensor with acomparatively smaller angle of view.

The optical sensors 150, 151, 152, and 153 may be arranged such that therespective field of view of each optical sensor 150, 151, 152, and 153overlaps with the field of view of another one of optical sensor 150,151, 152, and 153 along the perimeter frame. In some implementations,the optical sensors 150, 151, 152, and 153 are arranged such that thefield of view of each optical sensor 150, 151, 152, and 153 overlapswith the fields of view of two other optical sensors of the opticalsensors 150, 151, 152, and 153. For example, the field of view of thefirst optical sensor 150 and the field of view of the second opticalsensor 151 may have an overlap, and the field of view of the firstoptical sensor 150 and the fourth optical sensor 153 may have adifferent overlap. In addition, the field of view of the second opticalsensor 151 and the field of view of the third optical sensor 152 mayhave another, different overlap. The field of view of the third opticalsensor 152 and the field of view of the fourth optical sensor 153 mayhave yet another, different overlap.

As discussed below with respect to FIG. 5, optical sensors 150, 151,152, and 153 may communicate with and be controlled by control system,and signals from optical sensors 150, 151, 152, and 153 may includeimages or may be used to obtain images. In some implementations, theseimages may be processed to generate depth information, such as disparityand displacement, for objects included in the scene. The optical sensors150, 151, 152, and 153 may be coupled to the control system 114, forexample, via wires running through the front left corner junction 131-1,the front right corner junction 131-2, the rear right corner junction131-3, and the rear left corner junction 131-4, respectively. To reducedrag caused by the wires and/or to protect the wires, some or all of thewires may be located within cavities or space within the perimeterframe, such as within corner junctions 131. In some implementations, theoptical sensors 150, 151, 152, and 153 and the control system 114include wireless transmitter/receiver modules such that the opticalsensors 150, 151, 152, and 153 and the control system 114 maycommunicate wirelessly.

As discussed in more detail below with respect to FIGS. 2A, 2B, 3, and5, signals provided by optical sensors 150, 151, 152, and 153 may beused to generate a scene that is representative of a continuous spacethat horizontally surrounds the perimeter frame 104. In someimplementations, the scene may provide a 360-degree view of spacesurrounding the aerial vehicle 100 in a vertical, horizontal, or otherangle plane surrounding the aerial vehicle using as few as four cameras.For example, signals from only optical sensors 150, 151, 152, and 153may define a combined field of view that may be used by the controlsystem 114 to generate a scene representative of continuous space thathorizontally surrounds the aerial vehicle 100.

FIG. 2A depicts a partial view of a front portion 200 of an aerialvehicle, such as the aerial vehicle 100 discussed above with respect toFIG. 1. The front portion 200 includes a portion of a perimeter frame201. As discussed above with respect to FIG. 1, a winglet 221-1 and awinglet 221-2 may be coupled to and included as part of the portion ofthe perimeter frame 201 of the aerial vehicle. In this example, a firstoptical sensor 231 is attached to an outward facing portion 225 of thewinglet 221-1, and a second optical sensor 232 is attached to an inwardfacing portion 226 of the winglet 221-2. “Inward” and “outward” may bewith respect to the aerial vehicle.

In some implementations, the first optical sensor 231 and the secondoptical sensor 232 may be embedded (or “set”) inside the winglets 221-1and 221-2, respectively. For example, a portion of optical sensors 231and 232 may be located within a cavity or inner space of the winglets221, and/or coupled to an interior portion of the winglets 221. In otherimplementations, a portion of sensors (e.g. optical sensors 231 and 232)may be embedded in another structure or housing of the perimeter framesuch as a wing, flap, or corner junction, etc.

Embedding portions of the optical sensors 231 and 232 in structuresincluded in or attached to the perimeter frame can provide variousbenefits. For example, embedding optical sensors 231 and 232 into thewinglets 221-1 and 221-2 may reduce “dead spots” due to obstructionsbecause such embedding may reduce the overall footprint of the aerialvehicle. In addition, locating imaging elements, such as lenses, forexample, of the optical sensors 231 and 232 near exterior surfaces ofthe winglets 221 may allow the sensors to measure space close to thevehicle. Likewise, the low profile formed by embedding portions of theoptical sensors 231, 232 into the perimeter frame may reduce dragproduced from the optical sensors 231, 232 during operation of theaerial vehicle, thereby reducing overall power consumption requirementsof the aerial vehicle. Further, embedding the optical sensors 231, 232into structures of the perimeter frame 201 may allow for compatibilitywith different shaped optical sensor packages.

In some implementations, the optical sensors 231 and 232 are mounted onan outer surfaces of the perimeter frame 201 (e.g., winglets 221).Mounting the optical sensors 231 and 232 to the outer surface of theperimeter frame may be utilized for optical sensors with relativelysmall footprints that have minimal impact on aerial vehicle operation orblind spots. Also, mounting or locating optical sensors 231 and 232 onouter surfaces of the perimeter frame may require fewer modifications toan existing perimeter frame design.

Still referring to FIG. 2A, the first optical sensor 231 includes astereo camera having a first imaging element 240-1 and a second imagingelement 240-2 that may protrude away from the outward facing portion (or“side”) 225 of the winglet 221-1. The second optical sensor 232 includesa stereo camera having a first imaging element 241-1 and a secondimaging element 241-2 that may protrude away from the inward facingportion 226 of the winglet 221-2. For example, in implementations thatutilize stereo cameras, a portion of the optical sensors 231 and 232,such as lenses of imaging elements 240-1, 240-2, 241-1, and 241-2,protrude up to ⅜ inch away from an exterior surface of the winglets 221.

In some implementations, imaging elements 241-1, and 241-2 (e.g.,lenses) may be located proximate to outer edges of the winglets 221-1 tominimize “blind spots” caused by the winglets 221 and/or other parts ofthe perimeter frame 201. For example, in some implementations, a portion(e.g., a lens) of the optical sensors 231 and/or 232 may be locatedwithin ⅝ inch of a leading or trailing edge of the winglets 221. In someimplementations, a portion of the optical sensor 231 is within ⅝ of aninch of a trailing edge of winglet 221-1, and a portion of the opticalsensor 232 is within ⅝ of an inch of a trailing edge of winglet 221-2.

The first imaging element 240-1 and the second imaging element 240-2 ofthe first optical sensor 231 are vertically offset or spaced above andbelow with respect to one another along the winglet 221-1. In otherimplementations, the first imaging element 240-1 and the second imagingelement 240-2 may be horizontally offset, or spaced side to side, withrespect to one another. Likewise, the first imaging element 241-1 andthe second imaging element 241-2 of the second optical sensor 232 may behorizontally offset with respect to one another.

Vertically or horizontally offset imaging elements may be selected dueto, for example, a form factor or shape of a package of the stereocamera and/or a shape of the aerial vehicle, such as a shape of ahousing, structure, and/or frame to which the imaging elements areattached. In other implementations, pairs of imaging elements may beoffset in other directions with respect to one another. For example, thefirst imaging element 240-1 may be offset at any angle between ahorizontal offset and a vertical offset with respect to the position ofthe second imaging element 240-2 of the first optical sensor 231.

In addition, the desired fields of view of the stereo cameras mayinfluence whether horizontally or vertically offset stereo cameras areused. For example, the location of “blind spots” or areas where thefields of view of the imaging elements of the stereo camera do notoverlap (i.e., are not common), may depend on whether the imagingelements are offset vertically or horizontally.

A spacing or distance between imaging elements of a stereo camera, alsoreferred to as a baseline distance, may be adjusted depending on theintended use of the stereo camera. For example, increasing the baselinedistance between stereo cameras may provide improved depth sensingcapabilities moving away from the cameras. In comparison, decreasing thebaseline distance between the two imaging elements of the stereo pairpotentially improves depth sensing capabilities near the aerial vehicle.

The aerial vehicle may be asymmetrical due to the shape, location,orientation, and/or weight of the optical sensors. For example, asdiscussed above with respect to FIG. 2A, the first optical sensor 231may protrude away from an outward facing portion 225 of the winglet221-1, and the second optical sensor 232 may protrude away from ininward facing portion 226 of the winglet 221-2. Such asymmetries may becompensated for during aerial navigation by trimming a rudder, alteringthe rotational speed of one or more motors of the aerial vehicle, etc.

FIG. 2B depicts a partial view of a rear portion 202 of an aerialvehicle, such as the aerial vehicle 100 discussed above with respect toFIG. 1. The rear portion 202 includes a third optical sensor 233 and afourth optical sensor 234 that are mounted to the perimeter frame 201.The third optical sensor 233 protrudes away from an outer side 227 ofthe third winglet 221-3 and the fourth optical sensor 234 protrudes awayfrom an inner side 228 of the fourth winglet 221-4 of the perimeterframe 201. The third optical sensor 233 is a stereo camera that includesa first imaging element 242-1 and a second imaging element 242-2 thatare vertically offset. The fourth optical sensor 234 is a stereo camerathat includes a first imaging element 243-1 and a second imaging element243-2 that are vertically offset. It will be understood that the abovediscussions with respect to FIG. 2A may be applicable to the thirdoptical sensor 233 and the fourth optical sensor 234 of FIG. 2B,however, for the sake of brevity, these discussions will not berepeated.

The first imaging element 243-1 of the fourth optical sensor 234 has afirst field of view 252, and the second imaging element 243-2 has asecond field of view 254. The first imaging element 243-1 has ahorizontal angle of view 258-1 and a vertical angle of view 259-1. Thesecond imaging element 243-2 has a horizontal angle of view 258-2 and avertical angle of view 259-2. The fourth optical sensor 234 has a fieldof view 255 that is defined by an overlapping or a common portion of thefirst field of view 252 and the second field of view 254. The fourthoptical sensor 234 has a horizontal angle of view 260 and a verticalangle of view 281. It will be understood that the angles of view andfields of view of optical sensors 231 and 232 of FIG. 2A and the thirdoptical sensor 233 may be similar to the angles of view and fields ofview discussed above in connection with the fourth optical sensor 234.

In implementations where the horizontal angles of view 258-1 and 258-2are approximately equal, the horizontal angle of view 260 for the fourthoptical sensor 234 is approximately equal to the horizontal angles ofview 258-1 and 258-2. Similarly, if the vertical angles of view 259-1and 259-2 are approximately equal, the vertical field of view 281 forthe fourth optical sensor 234 is approximately equal to the verticalangles of view 259-1 and 259-2. In some implementations, optical sensors233 and 234 may have angles of view of at least 90 degrees. In someimplementations, the angle of view is approximately (e.g. +/−10%) anamount of sensors used divided by 360 degrees. In some implementations,the optical sensors 233 and 234 each have angles of view in onedirection (e.g., horizontal) of at least 100 degrees or at least 90degrees and angles of view in another direction (e.g., vertical) of atleast 60 degrees.

Optical sensors having particular angles of view may be selected to fordesired overlap between fields of view of optical sensors mounted to theaerial vehicle. Excess overlap in fields of view beyond what isnecessary to combine or stitch images together can be undesirablebecause such overlap may cause focus and distortion. Such overlap mayincrease the computing resources that are required to process thesignals output by the optical sensors.

FIG. 3 depicts an overhead-view of an aerial vehicle 300, in accordancewith an implementation. The aerial vehicle 300 includes a perimeterframe 399 that includes a front 392, a first side 394, a rear 396, and asecond side 398. In this example, the perimeter frame 399 isrectangular-shaped, but other sizes and shapes are possible. The aerialvehicle 300 also has a middle region 320 that may be located within thefront 392, the first side 394, the rear 396 and the second side 398. Forexample, the middle region 320 may correspond to a region defined by aradius (e.g., 5 inches) extending away from a center of mass or a centerof volume of the aerial vehicle 300.

The aerial vehicle 300 includes a first optical sensor 302, a secondoptical sensor 304, a third optical sensor 306, and a fourth opticalsensor 308. The optical sensors 302, 304, 306, and 308, in this example,are stereo cameras. The first optical sensor 302 and the second opticalsensor 304 may be secured or coupled to the front 392, and the thirdoptical sensor 306 and the fourth optical sensor 308 may be secured orcoupled to the rear 396. In one or more implementations, the front 392,the first side 394, the second side 398, or rear 396 may include one ormore structures that house or support the optical sensors 302, 304, 306,or 308, such as winglets wings, flaps, junctions, etc.

The first optical sensor 302, the second optical sensor 304, the thirdoptical sensor 306, and the fourth optical sensor 308 may have a firstfield of view 312, a second field of view 314, a third field of view316, and a fourth field of view 318, respectively. The first opticalsensor 302, the second optical sensor 304, the third optical sensor 306,and the fourth optical sensor 308 have a first horizontal angle of view382, a second horizontal angle of view 384, a third horizontal angle ofview 386, and a fourth horizontal angle of view 388, respectively.

A combined field of view 301 that includes fields of view 312, 314, 316,and 318 may include a continuous space that horizontally surrounds theperimeter frame 399 of the aerial vehicle 300. Blinds spots 352, 354,356, and 358 refer to regions between the optical sensors 302, 304, 306,and 308 and the fields of view 312, 314, 316, and 318 where depth maynot be sensed using a single stereo camera of the optical sensors 302,304, 306, and 308. For example, blind spots 352, 354, 356, and 358 maycorrespond to space where the fields of the view of imaging elements ofthe stereo cameras are not common, i.e., they do not overlap.

Sensing depth for a location using a stereo camera may require that theimaging elements have overlapping or common fields of view. In someimplementations, depth may be capable of being sensed in the blind spots352, 354, 356, and 358 using a combination of signals output fromadjacent optical sensors, such as 302 and 304. As discussed above withrespect to FIG. 2A, the size of blind spots 352, 354, 356, and 358 maybe adjusted or modified by using different types of sensors oradjustable sensors or reducing the baseline distance between the imagingelements of a stereo camera.

The optical sensors 302, 304, 306, and 308 are aligned in directionsindicated by the arrows 372, 374, 376, and 378 such that fields of view312, 314, 316, and 318 extend horizontally around the perimeter frame399 of the aerial vehicle 300, as illustrated. Likewise, each opticalsensor 302, 304, 306, and 308 is aligned (or “oriented”) such that atleast a portion of each adjacent field of view, such as the first fieldof view 312 and the second field of view 314, at least partiallyoverlap, as illustrated by an overlapping region (or “portion”) 334. Inone or more implementations, the second field of view 314 of the secondoptical sensor 304 overlaps with the third field of view 316 of thethird optical sensor 306 as illustrated by an overlapping region 336,the third field of view 316 of the third optical sensor 306 overlapswith the fourth field of view 318 of the fourth optical sensor 308, asillustrated by an overlapping region 338, and the fourth field of view318 also overlaps with the first field of view 312, as illustrated by anoverlapping region 332. Points 342, 344, 346, and 348 illustrate originsof the overlapping regions 332, 334, 336, and 338. As illustrated inFIG. 3, points 342, 344, 346, and 348 are horizontally separated awayfrom the perimeter (e.g. perimeter frame 399) of the aerial vehicle andmay be outside or not within the perimeter of the aerial vehicle. Insome implementations, the points 342, 344, 346, and 348 are horizontallyseparated away from the perimeter frame 399 by at least ½ inch.

In one or more examples, each of optical sensors 302, 304, 306, or 308is aligned as illustrated by alignment arrows 372, 374, 376, and 378that are directed away from aerial vehicle 300. In such an example,alignment arrows 372, 374, 376, and 378 may be directed approximatelyhalf-way along the respective horizontal angle of view so that aboundary (or “edge”) of the field of view is substantially parallel withthe corresponding edge of the aerial vehicle 300. For example, if ahorizontal angle of view for an optical sensor is 110 degrees, thealignment of the optical sensor, as illustrated by the alignment arrowis located at approximately half of 110 degrees, or 55 degrees withrespect to an edge of the aerial vehicle or the field of view. The edgeof the aerial vehicle may be defined by a front, a side, or a rear ofthe perimeter frame, for example.

Still referring to FIG. 3, in this example, first optical sensor 302 isoriented such that it is aligned, as illustrated by alignment arrow 372,approximately 45 degrees from a reference direction 311. Second opticalsensor 304 is oriented such that it is aligned, as illustrated byalignment arrow 374, approximately 135 degrees from the referencedirection 311. Third optical sensor 306 is oriented such that it isaligned, as illustrated by alignment arrow 376, approximately 225degrees with respect to the reference direction 311. Fourth opticalsensor 308 is oriented such that it is aligned, as illustrated byalignment arrow 378, approximately 315 degrees from the referencedirection 311.

The reference direction 311 may include any direction extending in avertical plane. In some implementations, the reference direction 311corresponds to a direction of travel or a forward direction traveled bythe aerial vehicle 300 when airborne and moving towards a destination.In some implementations, the reference direction 311 may correspond to adirection of travel provided, at least in part, by a thrusting motor,such as the rear thrusting motor 110-2 shown in FIG. 1. In someimplementations where the reference direction 311 corresponds to adirection of travel, as illustrated by the alignments arrows 372, 374,376, and 378, the first optical sensor 302, the second optical sensor304, the third optical sensor 306, and the fourth optical sensor 308 areoffset with respect to a direction of travel. For example, none of theoptical sensors 302, 304, 306, and 308 are aligned parallel with thereference direction 311.

In implementations that utilize a square shaped perimeter frame, forexample, the first optical sensor 302 may be adjacent to the fourthoptical sensor 308 and the second optical sensor 304. The second opticalsensor 304 may be adjacent to the third optical sensor 306 and the firstoptical sensor 302. The third optical sensor 306 may be adjacent to thesecond optical sensor 304 and the fourth optical sensor 308. The fourthoptical sensor 308 may be adjacent to the first optical sensor 302 andthe third optical sensor 306.

The first optical sensor 302 and the third optical sensor 306 may not beadjacent to one another. The first optical sensor 302 may be thefurthest of the optical sensors 302, 304, 306, and 308 from the thirdoptical sensor 306, and vice versa. The second optical sensor 304 andthe fourth optical sensor 308 may not be adjacent to one another. Thesecond optical sensor 304 may be the furthest of optical sensors 302,304, 306, and 308 from the fourth optical sensor 308, and vice versa.The first optical sensor 302 and the third optical sensor 306 may belocated across the middle region 320 of the aerial vehicle 300 from oneanother, and the second optical sensor 304 and the fourth optical sensor308 are located across the middle region 320 from one another.

Likewise, in some implementations, as illustrated by the alignmentarrows 372 and 376, the first optical sensor 302 may be aligned in anopposite direction with respect to the third optical sensor 306. Forexample, the alignment of the first optical sensor 302 and the alignmentof the third optical sensor 306 may be offset by approximately 180degrees (or “opposite”) with respect to one another. In a similarmanner, as illustrated by alignment arrows 374 and 378, the alignment ofthe second optical sensor 304 may be opposite the alignment of thefourth optical sensor 308. As illustrated by alignment arrows 374 and376, the alignment of the second optical sensor 304 and the alignment ofthe third optical sensor 306 may be offset by approximately 90 degreeswith respect to one another. In a similar manner, as illustrated byalignment arrows 372, 374, 376, and 378, the alignments of the firstoptical sensor 302 and the second optical sensors 304 may be offset byapproximately 90 degrees with respect to one another, the alignments ofthe second optical sensor 304 and the third optical sensor 306 may beoffset by approximately 90 degrees with respect to one another, thethird optical sensor 306 and the fourth optical sensor 308 may be offsetby approximately 90 degrees with respect to one another, and thealignment of the fourth optical sensor 308 and the alignment of thefirst optical sensor 302 may be offset approximately ninety degrees withrespect to one another.

By orienting and positioning each of the optical sensors as illustratedin FIG. 3, the signals provided by optical sensors 302, 304, 306, and308 may be used to generate a scene representative of a continuous spacethat horizontally surrounds the perimeter frame of the aerial vehiclehaving fewer or smaller size blind spots and while using fewer opticalsensors than prior art implementations. For example, the combined fieldof view 301 may include a 360-degree view around the vehicle.

Optical sensors having various fields of view may be used. While thereshould be some overlapping between adjacent fields of view to preventgaps between the fields of view, excessive overlapping fields of viewshould be avoided. Using optical sensors with larger fields of view maylead to increased distortion and higher processing requirements. In someimplementations, the first optical sensor 302 and the third opticalsensor 306 are sized, configured, and/or oriented such that theirrespective fields of view do not overlap. Similarly, the second opticalsensor 304 and the fourth optical sensor 308 may be sized, configured,and/or oriented such that their fields of view do not overlap. Forexample, the second optical sensor 304 and the fourth optical sensor 308may be selected to have angles of view that are less than 120 degrees.

As illustrated in FIG. 3, the first optical sensor 302 may be orientedand positioned such that the first field of view 312 includes spacesubstantially adjacent to the front 392 of the aerial vehicle 300. Forexample, the front 392 may include a flap, a wing, or a corner junction,such as the flap 127, the front wing 120, or one of corner junctions 130as discussed above with respect to FIG. 1. Similarly, the second opticalsensor 304 may be oriented and positioned such that the second field ofview 314 includes space substantially adjacent to the first side 394 ofthe aerial vehicle 300. For example, the first side 394 may include aside rail or a corner junction, such as the side rail 130 or the cornerjunction 131 as discussed above with respect to FIG. 1.

The third optical sensor 306 may be oriented and positioned such thatthe third field of view 316 includes space substantially adjacent to therear 396 of the aerial vehicle 300. For example, the rear 396 mayinclude a flap, a wing, or a corner junction, such as the upper rearwing 122, the lower rear wing 124, the flap 123, or one of cornerjunctions 130 as discussed above with respect to FIG. 1. The fourthoptical sensor 308 may be oriented and positioned such that the fourthfield of view 318 includes space substantially adjacent to the secondside 398 of the aerial vehicle 300. For example, the second side 398 mayinclude a side rail or a corner junction, such as a side rail 130 or acorner junction 131, as discussed above with FIG. 1.

As used herein, a field of view being “substantially adjacent” to astructure means that the field of view includes space that is 2 inchesor less from at least a portion of the structure, or an edge of thefield of view includes space that is less than 2 inches from at least aportion of the structure. For example, the first field of view 312includes space that is substantially adjacent to the front 392 if thefirst field of view 312 includes space that is 1.5 inches from a wing ofthe front 392.

In some implementations, one or more of the optical sensors 302, 304,306, and 308 are located and oriented such that their respective fieldsof view 312, 314, 316, and 318 include or overlap with a portion of thefront 392, the first side 394, the second side 398, or the rear 396 ofthe aerial vehicle 300, respectively. For example, as illustrated inFIG. 3, the third optical sensor 306 is positioned and oriented suchthat the third field of view 316 overlaps with or includes a portion ofthe rear 396 of the aerial vehicle 300.

Various aerial vehicle configurations are possible. For example, a scenemay be generated that is representative of a continuous space thatvertically surrounds a perimeter frame of an aerial vehicle. Forexample, two sensors may be attached to a first winglet and two sensorsmay be attached to a second winglet. The winglets may be locatedopposite one another on the perimeter frame (front/back or oppositesides), and the sensors on each winglet may be vertically offset fromone another. The field of view of each sensor overlaps with fields ofview of two of the other sensors. Some or all of the overlapping fieldshave origins that are extended away vertically from the perimeter of theaerial vehicle, and a combined field of view of the fields of view ofthe plurality of sensors includes space that vertically surrounds theperimeter of the aerial vehicle.

Likewise, various aerial vehicle configurations may be utilized. Forexample, “octo-copter,” octagon, or circular-shaped perimeter frames maybe utilized. Different numbers of optical sensors may be utilized. Insome implementations, five optical sensors may be coupled along aperimeter frame. In another example, an aerial vehicle may have a sensorat each of eight locations along a perimeter frame. In someimplementations, eight sensors are arranged along a perimeter frame andthe angle of view of each sensor is between 45 and 55 degrees.

In yet another example, an aerial vehicle may utilize six opticalsensors located at locations (e.g., each corner) of a hexagon-shapedperimeter frame. In some implementations, a plurality of optical sensorsmay each be aligned vertically such that an alignment of each opticalsensor is directed opposite (e.g., offset by approximately 180 degrees)an alignment of another optical sensor.

FIG. 4 shows an aerial vehicle 402 that has an optical sensor 403 thatis oriented in a downward facing direction and a “vertical” field ofview 404 that includes space below the aerial vehicle 402. Opticalsensor 403 may be a stereo camera. In some implementations, a portion ofthe optical sensor 403 may be embedded in a cavity of a structure of theaerial vehicle and a portion may protrude from a surface of thestructure. The optical sensor 403 may be included, for example, in theaerial vehicle 100 or the aerial vehicle 300 discussed above withrespect to FIGS. 1 and 3, respectively. Providing the optical sensor 403in combination with the optical sensors depicted in FIG. 1 or 3, mayprovide for a combined field of view in the horizontal anddownward-facing vertical directions using as few as five cameras, whichis fewer cameras than existing designs.

In some implementations, the aerial vehicle 402 includes an additionaloptical sensor that is oriented in an upward facing direction and avertical field of view that includes space above the aerial vehicle 402.Such a configuration in combination with the optical sensors depicted inFIG. 1 or 3, may provide for a combined field of view that correspondsto space that horizontally and vertically surrounds the aerial vehicleusing as few as six optical sensors.

In some implementations, a plurality of optical sensors may be coupledto the aerial vehicle 402 in a similar manner as discussed in connectionwith FIGS. 1 and 3, except they are arranged to provide a scene that isrepresentative of a continuous space that vertically surrounds theaerial vehicle. For example, a boundary (or “edge of the field”) of atleast one field of view of the plurality of fields of view issubstantially adjacent to a top, a bottom, and sides of the aerialvehicle. The four sensors may be oriented such that portions of fieldsof view of adjacent sensors overlap such that a combined or overallfield of view include a continuous space that vertically surrounds theaerial vehicle. A scene that is representative of the continuous spacethat vertically surrounds the aerial vehicle may be generated from thefour sensors.

FIG. 5 is a flow diagram illustrating an example process for generatinga scene representative of a continuous space that horizontally surroundsthe perimeter frame, according to an implementation. The process of FIG.5 and each of the other processes and sub-processes discussed herein maybe implemented in hardware, software, or a combination thereof. In thecontext of software, the described operations representcomputer-executable instructions stored on one or more computer-readablemedia that, when executed by one or more processors, perform the recitedoperations. Generally, computer-executable instructions includeroutines, programs, objects, components, data structures, and the likethat perform particular functions or implement particular abstract datatypes.

The computer-readable media may include non-transitory computer-readablestorage media, which may include hard drives, floppy diskettes, opticaldisks, CD-ROMs, DVDs, read-only memories (ROMs), random access memories(RAMs), EPROMs, EEPROMs, flash memory, magnetic or optical cards,solid-state memory devices, or other types of storage media suitable forstoring electronic instructions. In addition, in some implementationsthe computer-readable media may include a transitory computer-readablesignal (in compressed or uncompressed form). Examples ofcomputer-readable signals, whether modulated using a carrier or not,include, but are not limited to, signals that a computer system hostingor running a computer program can be configured to access, includingsignals downloaded through the Internet or other networks. Finally, theorder in which the operations are described is not intended to beconstrued as a limitation, and any number of the described operationscan be combined in any order and/or in parallel to implement theprocess.

The example process 500 receives signals from a plurality of opticalsensors around an aerial vehicle, as in 502. For example, the aerialvehicle may be the aerial vehicle 100 depicted in FIG. 1 or the aerialvehicle 300 that is depicted in FIG. 3. In some implementations, signalsmay be received from four optical sensors. One or more of the fouroptical sensors may be a stereo camera, and signals from the fouroptical sensors may be images or may be used to generate images.

In some implementations, at least a portion of each of the opticalsensors may be mounted to a perimeter frame of the aerial vehicle, todifferent winglets extending from the perimeter frame, and/or otherstructures that are coupled to the perimeter frame. Likewise, wiredand/or wireless communications may couple each optical sensor to anaerial vehicle control system. Wired communications may be located inthe winglets and/or the other structure of the aerial vehicle. Thesignals may pass from the optical sensors to the aerial vehicle controlsystem via the wired and/or wireless communications such that thesignals may be received from the optical sensors via the wired and/orwireless communications.

As discussed with respect to FIGS. 1, 2A, 2B, and 3, the fields of viewof adjacent optical sensors may at least partially overlap such that thesignals include information for a common space where the fields of viewof adjacent optical sensors overlap. For example, referring back to FIG.1, a first portion of a first signal from the first optical sensor 150and a second portion of a second signal from a second optical sensor 151represent a first same space with respect to the aerial vehicle 100.Similarly, a third portion of the second signal and a fourth portion ofa third signal from the third optical sensor 152, represent a secondsame space with respect to the aerial vehicle, a fifth portion of thethird signal and a sixth portion of a fourth signal from the fourthoptical sensor 153 represent a third same space; and a seventh portionof the fourth signal and an eighth portion of the first signalrepresents a fourth same space.

At block 504, a scene that is representative of a continuous space thathorizontally surrounds the perimeter frame of the aerial vehicle isgenerated by processing the signals from around the aerial vehicle.Various currently known or later developed image processing techniquesmay be used to generate the scene. In some implementation, imagestitching may be used to generate the scene. The scene may be stored ina memory of an aerial vehicle control system and/or transmitted to aremote location, such as a remote computing resource.

In addition, or as an alternative to receiving signals from theplurality of optical sensors, SONAR, and/or other like components, maybe used to detect a presence of an object within a distance of theaerial vehicle. In some implementations, rather than using images fromstereo cameras, images from single lens cameras positioned around theaerial vehicle in a manner discussed above may be obtained and processedto generate a horizontal scene around the aerial vehicle and/orprocessed to determine a presence of a potential object. Pixel valuesmay be compared between images to detect changes in view that mayrepresent an object. In some implementations, if a potential object isdetected, additional processing, using images from others opticalsensors, etc., may be utilized to determine a presence of an object.

Based on the generated scene, a determination is made whether an objecthas been detected, as in 506. Objects may be detected using currentlyknown object detection techniques, such as edge detection, shapedetection, gray scale detection, or later developed techniques. If it isdetermined that an object has not been detected, the example process 500returns to block 502 and continues.

At block 508, the detected object may be evaluated. Evaluating an objectmay involve determining at least one of a size, a shape, a type, acategory, a velocity, an acceleration, a position, or a distance relatedto the detected object. The object may be evaluated, for example, bydetermining an approximate distance between the object and the aerialvehicle. For example, the generated scene may be compared with a knownbaseline to determine an approximate distance between the object and theaerial vehicle. The approximate distance between the object and theaerial vehicle may be monitored over time. In some examples, an objectmay be tracked. Such tracking of a detected object may repeat the blocks502-506, receiving additional signals, processing those signals anddetecting/tracking the object as the object moves. In some examples, adetected object is added to a map and the position of the object may beupdated in the map. In other implementations, upon object detection, oneor more characteristics of the object may be determined (e.g., size,shape, color) and additional signal from the imaging elements and/oroptical sensors that detected the object may be processed to detect thedetermined characteristics about the object. Upon detection of thosecharacteristics in subsequent signals, object tracking may be maintainedwith limited processing demand.

Based on the tracking, a determination is made whether to perform anaction, as in block 510. An action may be determined to be performed ifthe approximate distance between the object and the aerial vehicle dropsbelow a particular amount or the distance between the object and theaerial vehicle is decreasing more than a threshold level. If it isdetermined to not perform an action, the example process 500 returns toblock 502 and continues.

At block 512, an action may be determined and performed. In someimplementation, the action is determined based on tracking the object.For example, if an object is determined to be rapidly approaching thevehicle at about the same level of the vehicle, a command may begenerated that causes the aerial vehicle to gain altitude (an action)such that the aerial vehicle maintains a safe distance from the object.In some implementations, an action is determined due to an object beingdetected that obstructs a planned path or landing area, and an action toadjust the flight path is performed. For example, if an object (e.g., acar) is determined to be at a planned landing zone, another landing zonemay be determined and navigation of the aerial vehicle updatedaccordingly. It will be appreciated that any type of navigation,maneuver, ascend, descend, etc. performed by the aerial vehicle orupdating a flight plan for the aerial vehicle may be considered anaction performed as part of the example process 500.

While the examples discussed herein describe use of the implementationswith an aerial vehicle, such as a UAV, it will be appreciated that thedescribed implementations may likewise be used with other vehiclesand/or in other scenarios. For example, a plurality of optical sensorsmay be positioned on another type of vehicle, such as a ground basedand/or water based vehicle and an optical sensor selection controllerutilized to select a combination of optical sensors, as discussed above.

FIG. 6 is a block diagram illustrating an example aerial vehicle controlsystem 600. In various examples, the block diagram may be illustrativeof one or more aspects of the aerial vehicle control system 600 that mayimplement the systems and methods discussed and/or to control operationof the aerial vehicles described herein. In the illustratedimplementation, the aerial vehicle control system 600 includes one ormore processors 602, coupled to a memory, e.g., a non-transitorycomputer readable storage medium 620, via an input/output (I/O)interface 610. The aerial vehicle control system 600 may also includeelectronic speed controls 604 (ESCs), power supply modules 606, anavigation system 607, and/or a payload engagement controller 612. Insome implementations, the navigation system 607 may include an inertialmeasurement unit (IMU). The aerial vehicle control system 600 may alsoinclude a network interface 616, and one or more input/output devices618.

The aerial vehicle control system 600 may also include the opticalsensor controller 614 that communicates with the plurality of opticalsensors. The optical sensor controller 614 is communicatively coupled tothe optical sensors via a wired or wireless coupling. In someimplementations, the optical sensor controller 614 may receive signals(e.g. images) from the optical sensors. The optical sensor controller614 may also control the optical sensors. For example, the opticalsensor controller 614 may be configured to control a rate of operation(e.g., number of frames/second), shutter speed, and/or a focus of theoptical sensors. In some implementations, the optical sensor controller614 may control image stabilizing mechanisms coupled to or incorporatedinto the optical sensors. In some implementations, the optical sensorcontroller 614 may be able to process (e.g. filter) signals or imagesprovided by the optical sensors.

In implementations that utilize LIDAR, for example, the optical sensorcontroller 614 may be configured to control characteristics of lightthat is used to illuminate a target space. For example, the opticalsensor controller 614 may be configured to control the intensity orfrequency of the emitted light and/or the rate of the scanning thereceived light. For example, optical sensor controller 614 may cause theintensity of the emitted light to be greater when the vehicle istraveling close to the ground where objects are more likely to bepresent.

In various implementations, the aerial vehicle control system 600 mayinclude a uniprocessor system including one processor 602, or amultiprocessor system including more than one processor 602 (e.g., two,four, eight, or another suitable number). The processor(s) 602 may beany suitable processor capable of executing instructions. For example,in various implementations, the processor(s) 602 may be general-purposeor embedded processors implementing any of many instruction setarchitectures (ISAs), such as the x86, PowerPC, SPARC, or MIPS ISAs, orany other suitable ISA. In multiprocessor systems, each processor(s) 602may commonly, but not necessarily, implement the same ISA.

The non-transitory computer readable storage medium 620 may beconfigured to store executable instructions, data, flight paths, flightcontrol parameters, and/or data items accessible by the processor(s)602. Data items may include, for example, images obtained from one ormore of the optical sensors, distance information, combined imageinformation (e.g., depth information), etc.

In various implementations, the non-transitory computer readable storagemedium 620 may be implemented using any suitable memory technology, suchas static random access memory (SRAM), synchronous dynamic RAM (SDRAM),nonvolatile/Flash-type memory, or any other type of memory. In theillustrated implementation, program instructions and data implementingdesired functions, such as those described herein, are shown storedwithin the non-transitory computer readable storage medium 620 asprogram instructions 622, data storage 624 and flight controls 626,respectively. In other implementations, program instructions, data,and/or flight controls may be received, sent, or stored upon differenttypes of computer-accessible media, such as non-transitory media, or onsimilar media separate from the non-transitory computer readable storagemedium 620 or the aerial vehicle control system 600. Generally, anon-transitory, computer readable storage medium may include storagemedia or memory media such as magnetic or optical media, e.g., disk orCD/DVD-ROM, coupled to the aerial vehicle control system 600 via the I/Ointerface 610. Program instructions and data stored via a non-transitorycomputer readable medium may be transmitted by transmission media orsignals, such as electrical, electromagnetic, or digital signals, whichmay be conveyed via a communication medium such as a network and/or awireless link, such as may be implemented via the network interface 616.

In one implementation, the I/O interface 610 may be configured tocoordinate I/O traffic between the processor(s) 602, the non-transitorycomputer readable storage medium 620, and any peripheral devices, thenetwork interface 616 or other peripheral interfaces, such asinput/output devices 618. In some implementations, the I/O interface 610may perform any necessary protocol, timing or other data transformationsto convert data signals from one component (e.g., non-transitorycomputer readable storage medium 620) into a format suitable for use byanother component (e.g., processor(s) 602). In some implementations, theI/O interface 610 may include support for devices attached throughvarious types of peripheral buses, such as a variant of the PeripheralComponent Interconnect (PCI) bus standard or the Universal Serial Bus(USB) standard, for example. In some implementations, the function ofthe I/O interface 610 may be split into two or more separate components,such as a north bridge and a south bridge, for example. Also, in someimplementations, some or all of the functionality of the I/O interface610, such as an interface to the non-transitory computer readablestorage medium 620, may be incorporated directly into the processor(s)602.

The ESCs 604 communicate with the navigation system 607 and adjust therotational speed of each lifting motor and/or the thrusting motor tostabilize the UAV and guide the UAV along a determined flight path. Thenavigation system 607 may include a GPS, indoor positioning system(IPS), IMU or other similar systems and/or sensors that can navigate theaerial vehicle 100 to and/or from a location. The payload engagementcontroller 612 communicates with actuator(s) or motor(s) (e.g., a servomotor) used to engage and/or disengage items.

The network interface 616 may be configured to allow data to beexchanged between the aerial vehicle control system 600, other devicesattached to a network, such as other computer systems (e.g., remotecomputing resources), and/or with aerial vehicle control systems ofother UAVs. For example, the network interface 616 may enable wirelesscommunication between the UAV that includes the control system 600 andan aerial vehicle control system that is implemented on one or moreremote computing resources. For wireless communication, an antenna of anUAV or other communication components may be utilized. As anotherexample, the network interface 616 may enable wireless communicationbetween numerous UAVs. In various implementations, the network interface616 may support communication via wireless general data networks, suchas a Wi-Fi network. For example, the network interface 616 may supportcommunication via telecommunications networks, such as cellularcommunication networks, satellite networks.

Input/output devices 618 may, in some implementations, include one ormore displays, imaging devices, thermal sensors, infrared sensors, timeof flight sensors, accelerometers, pressure sensors, weather sensors,optical sensors (e.g., cameras), gimbals, landing gear, etc. Multipleinput/output devices 618 may be present and controlled by the aerialvehicle control system 600. One or more of these sensors may be utilizedto assist in landing as well as to avoid obstacles during flight.

As shown in FIG. 6, the memory may include program instructions 622,which may be configured to implement the example routines and/orsub-routines described herein. The data storage 624 may include variousdata stores for maintaining data items that may be provided fordetermining flight paths, landing, identifying locations for disengagingitems, engaging/disengaging the thrusting motors, selecting acombination of optical sensors for stereo imaging, etc. In variousimplementations, the parameter values and other data illustrated hereinas being included in one or more data stores may be combined with otherinformation not described or may be partitioned differently into more,fewer, or different data structures. In some implementations, datastores may be physically located in one memory or may be distributedamong two or more memories.

Those skilled in the art will appreciate that the aerial vehicle controlsystem 600 is merely illustrative and is not intended to limit thepresent disclosure. In particular, the computing system and devices mayinclude any combination of hardware or software that can perform theindicated functions. The aerial vehicle control system 600 may also beconnected to other devices that are not illustrated, or instead mayoperate as a stand-alone system. In addition, the functionality providedby the illustrated components may, in some implementations, be combinedin fewer components or distributed in additional components. Similarly,in some implementations, the functionality of some of the illustratedcomponents may not be provided and/or other additional functionality maybe available.

Those skilled in the art will also appreciate that, while various itemsare illustrated as being stored in memory or storage while being used,these items or portions of them may be transferred between memory andother storage devices for purposes of memory management and dataintegrity. In other implementations, some or all of the softwarecomponents may execute in memory on another device and communicate withthe illustrated aerial vehicle control system 600. Some or all of thesystem components or data structures may also be stored (e.g., asinstructions or structured data) on a non-transitory,computer-accessible medium or a portable article to be read by anappropriate drive. In some implementations, instructions stored on acomputer-accessible medium separate from the aerial vehicle controlsystem 600 may be transmitted to the aerial vehicle control system 600via transmission media or signals such as electrical, electromagnetic,or digital signals, conveyed via a communication medium such as awireless link. Various implementations may further include receiving,sending, or storing instructions and/or data implemented in accordancewith the foregoing description upon a computer-accessible medium.Accordingly, the techniques described herein may be practiced with otheraerial vehicle control system configurations.

Although the subject matter has been described in language specific tostructural features and/or methodological acts, it is to be understoodthat the subject matter defined in the appended claims is not limited tothe specific features or acts described. Rather, the specific featuresand acts are disclosed as exemplary forms of implementing the claims.

What is claimed is:
 1. An unmanned aerial vehicle (UAV), comprising: aperimeter frame having a front portion and a rear portion; a firstoptical sensor having a first field of view, the first optical sensorcoupled at a first location to the front portion of the perimeter frameand having a first orientation; a second optical sensor having a secondfield of view, the second optical sensor coupled at a second location tothe front portion of the perimeter frame and having a second orientationsuch that at least a first portion of the second field of view overlapswith at least a first portion of the first field of view; a thirdoptical sensor having a third field of view, the third optical sensorcoupled at a third location to the rear portion of the perimeter frameand having a third orientation such that at least a first portion of thethird field of view overlaps with at least a second portion of thesecond field of view; a forth optical sensor having a fourth field ofview, the fourth optical sensor coupled at a fourth location to the rearportion of the perimeter frame and having a fourth orientation suchthat: at least a first portion of the fourth field of view overlaps withat least a second portion of the third field of view; and at least asecond portion of the fourth field of view overlaps with at least asecond portion of the first field of view; one or more processors; and amemory including program instructions that when executed by the one ormore processors causes the one or more processors to at least process asignal from each of the first optical sensor, the second optical sensor,the third optical sensor, and the fourth optical sensor to generate ascene representative of a continuous space that horizontally surroundsthe perimeter frame.
 2. The UAV of claim 1, wherein: the first opticalsensor includes a first stereo camera; the second optical sensorincludes a second stereo camera; the third optical sensor includes athird stereo camera; and the fourth optical sensor includes a fourthstereo camera.
 3. The UAV of claim 2, wherein: the first optical sensorhas a first angle of view that is greater than 90 degrees, the secondoptical sensor has a second angle of view that is greater than 90degrees, the third optical sensor has a third angle of view that isgreater than 90 degrees, and the fourth optical sensor has a fourthangle of view that is greater than 90 degrees.
 4. The UAV of claim 2,wherein the first stereo camera and the second stereo camera arepositioned such that a first alignment of a first angle of view of afirst optical sensor and a second alignment of a second angle of view ofthe third optical sensor are directed substantially opposite each other.5. An aerial vehicle, comprising: a perimeter frame having a frontportion and a rear portion; a first sensor having a first field of view,the first sensor coupled to the front portion; a second sensor having asecond field of view, the second sensor coupled to the front portion; athird sensor having a third field of view, the third sensor coupled tothe rear portion; a fourth sensor having a fourth field of view, thefourth sensor coupled to the rear portion; and wherein: the fourthsensor is oriented such that an edge of the fourth field of view issubstantially adjacent to a first structure that houses the firstsensor; the first sensor is oriented such that an edge of the firstfield of view is substantially adjacent to a second structure thathouses the second sensor; the second optical sensor is oriented suchthat an edge of the second field of view is substantially adjacent to athird structure that houses the third sensor; and the third sensor isoriented such that an edge of the third field of view is substantiallyadjacent to a fourth structure that houses the fourth sensor.
 6. Theaerial vehicle of claim 5, wherein the first field of view and the thirdfield of view do not overlap.
 7. The aerial vehicle of claim 5, wherein:a first portion of the first field of view and a first portion of thesecond field of view overlap outside the perimeter frame; a secondportion of the second field of view and a first portion of the thirdfield of view overlap outside the perimeter frame; a second portion ofthe third field of view and a first portion of the fourth field of viewoverlap outside the perimeter frame; and a second portion of the fourthfield of view and a second portion of the first field of view overlapoutside the perimeter frame.
 8. The aerial vehicle of claim 5, wherein:the first structure includes a first winglet; the second structureincludes a second winglet; the third structure includes a third winglet;and the fourth structure includes a fourth winglet.
 9. The aerialvehicle of claim 8, wherein: the first sensor protrudes from an innerportion of the first winglet; the second sensor protrudes from an outerportion of the second winglet; the third sensor protrudes from an innerportion of the third winglet; and the fourth sensor protrudes from anouter portion of the fourth winglet.
 10. The UAV of claim 5, furthercomprising a propulsion device configured to selectively move the UAV ina direction of travel, wherein the first sensor is positioned such thatan alignment of a first angle of view extends in a direction that isoffset from a horizontal direction of travel.
 11. The aerial vehicle ofclaim 5, wherein: the first sensor includes a first stereo camera; thesecond sensor includes a second stereo camera; the third sensor includesa third stereo camera; and the fourth sensor includes a fourth stereocamera.
 12. The aerial vehicle of claim 11, wherein at least one of thefirst stereo camera, the second stereo camera, the third stereo camera,or the fourth stereo camera includes a first imaging element and asecond imaging element that are vertically offset from one another. 13.The aerial vehicle of claim 11, wherein at least one of the first stereocamera, the second stereo camera, the third stereo camera, or the fourthstereo cameras includes a first imaging element and a second imagingelement that are horizontally offset from one another.
 14. The UAV ofclaim 5, wherein: the perimeter frame has a first side with a firstouter surface and a second side having a second outer surface; at leasta portion of an edge of the first field of view overlaps with the firstouter surface of the first side of the perimeter frame; at least aportion of the edge of the second field of view overlaps with the secondouter surface of the first side of the perimeter frame; and the firstand second sides are opposite one another.
 15. The aerial vehicle ofclaim 5, wherein a first location of the first sensor and a secondlocation of the second sensor are on a lower portion of the perimeterframe, and a third location of the third sensor and a fourth location ofthe fourth sensor are on an upper portion of the perimeter frame. 16.The aerial vehicle of claim 5, wherein: the first sensor is configuredto provide a first signal; the second sensor is configured to provide asecond signal, the third sensor is configured to provide a third signal;the fourth sensor is configured to provide a fourth signal; and acombination of the first signal, the second signal, the third signal,and the fourth signal is representative of at least a continuous spacethat horizontally surrounds the perimeter frame.
 17. The aerial vehicleof claim 5, further comprising: a fifth sensor that is coupled to theperimeter frame and oriented such that: the fifth sensor has a fifthfield of view that is at least one of: representative of at least one ofa vertical space below the perimeter frame; or representative of avertical space above the perimeter frame.
 18. A computer-implementedmethod of generating a scene that represents a continuous spacehorizontally surrounding a perimeter frame of an aerial vehicle,comprising: receiving a first signal from a first optical sensor,wherein the first optical sensor protrudes from an inner portion of afirst winglet that is coupled to the perimeter frame; receiving a secondsignal from a second optical sensor, wherein the second optical sensorprotrudes from an outer portion of a second winglet that is coupled tothe perimeter frame; receiving a third signal from a third opticalsensor, wherein the third optical sensor protrudes from a third wingletthat is coupled to the perimeter frame; receiving a fourth signal from afourth optical sensor, wherein fourth optical sensor protrudes from afourth winglet that is coupled to the perimeter frame; and processingthe first signal, the second signal, the third signal, and the fourthsignal to generate the scene that represents the continuous spacesurrounding the perimeter frame of the UAV.
 19. The computer-implementedmethod of claim 18, wherein: the first optical sensor comprises a firststereo camera; the second optical sensor comprises a second stereocamera; the third optical sensor comprises a third stereo camera; andthe fourth optical sensor comprises a fourth stereo camera.
 20. Thecomputer-implemented method of claim 18, wherein: a first portion of thefirst signal and a second portion of the second signal represents afirst same space; a third portion of the second signal and a fourthportion of the third signal represents a second same space; a fifthportion of the third signal and a sixth portion of the fourth signalrepresents a third same space; and a seventh portion of the fourthsignal and an eighth portion of the first signal represents a fourthsame space.